primary care physician vs doc

primary care physician and doc both are nouns.

Word	Noun	Adjective	Verb	Adverb
primary care physician	Yes	No	No	No
doc	Yes	No	No	No

As nouns, doc is a hypernym of primary care physician; that is, doc is a word with a broader meaning than primary care physician:

Other hypernyms of primary care physician include doctor, Dr., MD, medico, physician.

primary care physician (noun)	doc (noun)
the physician who provides primary care	a licensed medical practitioner